Choke or ballast and frame therefor



Patented Dec. 2, 1947.

CHOKE R BALLAST AND FRAME THEREFOR Joseph J. Galla, Fair-field, Conn.,assignor to The Stratfield Company, Bridgeport, Conn., a corporation ofConnecticut Application July 26, 1945, Serial No. 607,147

16 Claims. 1

This invention relates to new and useful improvements in chokes orballasts and frame therefor.

An object of the invention is to provide a choke or ballast including amechanical construction or frame for holding the coil together with theE- and I-laminations firmly in place whereby the space or air-gapbetween such laminations is maintained constant to the end that there isa constant output from the device.

Another object is to provide a choke or ballast, as stated, and whereinthe mechanical construction or frame provides for the secure wedging ofa center arm of the E-laminations in the surrounding coil and the tightclamping together of the free ends of the outside arms of theE-larninations whereby hum or vibration is prevented.

Other objects and advantages of the invention will become apparent froma consideration of the following detailed description taken inconnection with the accompanying drawing wherein a satisfactoryembodiment of the invention is shown. However, it is to be understoodthat the invention is not limited to the details disclosed but includesall such variations and modifications as fall within the spirit of theinvention and the scope of the appended claims.

In the drawing:

Fig. 1 is a plan view of the blank from which the frame of the inventionis to be formed;

Fig. 2 is an edge view of the same;

Fig, 3 is a view looking into the open end of the formed or bent-upframe;

Fig. 4 is a side elevational view of such frame;

Fig. 5 is a top plan view of the completed ballast or choke;

Fig. 6 is a side elevational View of the same; and

Fig. 7 is a sectional view taken as along the line 1-'! of Fig. 6.

Referring in detail to the drawing, the blank, generally designated ID,of Figs. 1 and 2, comprises a pair of side portions II and 12, eachincluding a rail or wall-like portion l3 and an arm or extension l4.Between the side portions I l and I2 is a bight portion includingmounting ears l5, each perforated, as shown, for the passage of securingscrews or the like and a spring tongue portion 16.

The side portions l l and I2 are connected with portion I6 along thefold lines indicated by the dotted lines ll in Fig. 1 so that the endportions of IS arefree and such end portions provide spring lugs as willhereinafter appear. Additionally, side portions H and I2 are connected 2with the ears [5 along the fold lines l8, which lines are, of course, inalignment with the fold lines I! at the respective edges of portion l6.

Each of the extensions M has a bead l9 pressed outwardly therefromadjacent its inner end in parallel relation with the portion l6 andoutwardly of such bead has a pair of longitudinally extending beads 20placed outwardly therefrom and arranged in parallel relation with oneanother. Adjacent its outer or free end each extension M has an openingor perforation 2! for the passage of a rivet or the like as will appear.Side portions l3 adjacent their ends include ear-like extensions 22.

When the blank is folded as along the fold. lines H and 18, a generallyU-shaped structure is provided and prior to the actual folding theportion I5 is set up whereby its free end portions 23 comprise springlugs. In the completed choke or ballast the E-laminations 24 have theirconnecting portions located between the free end portions of theextensions l4 and a rivet 25 passes through the openings 2| in suchextensions and through such portions of the laminations forcing thelatter tight tog-ether and securing the frame in place.

The I-laminations 26 are disposed between the side wall portions 13 ofthe frame and are separated from the free ends of the arms oflaminations 24 by any suitable separator 21. The coil 28 is not onlyabout the center arm of the E- laminations but is also about theextensions 14 of the mechanical frame. In making the assembly, theI-laminations 26 are forced against the spring lugs 23 flattening orsubstantially flattening the latter and so when the rivet 25 is in placethe E-laminations are held and the spring lugs exert a continuouspressure on the I-laminations 26 forcing them against the spacer 21.

This result is further enhanced by the expansion loops or beads I9 whichare somewhat flattened when holding the parts together to position therivet 25. The beads or embossed webs 20 of the extension l4 result inthe creation of a pressure between the inner walls of the coil 28 andthe central leg of the E-laminations.

Additionally, the ears or extensions 22 of the frame press against thefree end portions of the outer arms of the E-laminations so that suchportions are, in effect, clamped between the ears or extensions 22 atone side of the laminations 24 and those at the other side thereof.Thus, the entire assembly is tightly held and the clamping action by thecars 22 prevents vibration or hum.

With the described construction, it will be aptensions arranged inparallel relation, an outwardly pressed transversely extended beadsubstantially at the juncture of each of said extensions with its sideportion, and a spring lug integral with said bight portion.

16. In a ballast or choke, a first body of E- laminations, a second bodof I-laminations, a frame including spaced arms and a connecting bightportion, said bodies disposed between the arms of the frame with thesecond body against said bight portion, means passing through the freeend portions of said arms and the back portion of the first body andrigidly connecting said arms and portion, insulation between the freeends of the arms of the first body and the second body, a coil about thearms of said frame and the central arm of the first body, and resilientmeans carried by said bight portion and constantly urging the secondbody against said insulation.

JOSEPH J. GALLA.

REFERENCES CITED The following references are of record in the file ofthis patent:

